This invention relates to an upper cloth feed device for sewing machines which forms seams in multiple pieces of cloth consisting of an upper cloth and lower cloths. More particularly, the invention contemplates providing an upper cloth feed device which permits any type of presser foot shank which is attached to a presser bar of a sewing machine to be removably fitted with the upper cloth feed device after a shoe is removed from the shank.
An upper cloth feed device of the prior art will be described hereinafter, referring to FIG. 6 and invented by the same inventor as disclosed in Japanese Utility Model Publication No. 1982-13003. The upper cloth feed device includes a body 50 which has an upper cloth feeding foot 52, a cloth presser 54, a lever foot 56 and a lever 58. The body 50 has a groove 50b into which a presser foot of a sewing machine (not shown) can be fixedly positioned and a pair of foot portions 50a. The upper cloth feeding foot 52, provided with two-forked portions 52a and 52b, is disposed underneath the foot portion 50a and is slidably held on the end of the body 50. The upper cloth feeding foot 52 is also urged upwardly relative to the body 50 by a coil spring (not shown). One end of the lever foot 56 is pivotably connected to the lever 58 which is pivotably supported by the body 50 by a vertical stand 60 while the other end 56a is positioned on the cloth presser 54 which is located between the two-forked feet 52a and 52b. The cloth presser 54 is also connected to the body 50 by coil spring 55. One end of the lever 58 is provided with a slit 58a which can hold a projection 32a of a needle clamp 32 of a needle bar 31, as shown in FIG. 1. The lever 58 is shifted up and down simultaneously with up and down motion of the needle bar 31. When the lever 58 is shifted downward, the upper cloth feed foot 52 is pushed on the upper cloth, aided by pushing down movement of a presser bar 37, as shown in FIG. 2, fitted on the body 50, and shifted backward to feed the upper cloth in the same direction, while during transitory movement from downward to upward shifting of the lever 58, the presser 54 is pushed onto the upper cloth whereby the upper cloth feeding foot 52 is lifted upward to be shifted back to its former position.
The upper cloth feed device of the prior art described above is attached to the sewing machine presser foot and performs feeding of an upper cloth of multiple layer materials consisting of a lower cloth on which an upper cloth is placed, in conjunction with forming seams in the materials. It is a common occurrence that a single layer material is sewn by a sewing machine, at which time a presser foot fitted with a removable shoe is used. Therefore, when an operator intends to perform sewing double or multiple layer materials, he has to remove the presser foot assembly for a single layer material which has heretofore been explained from the sewing machine presser bar and replace it with the upper cloth feed device.